Letter from Business( company) of B1 visa holder to the consulate endorsing and requesting the visa for B1 holders family may also help.

Other suggested documents for visitor visa

Occupation related: If you are employed, get a letter of employment verification.

If you are a government employee, you must get a NOC.

If you are self-employed, you must get proof of business ownership and financial history.

Note: The above list of documents is not mandatory, and depending on individual circumstance, some of these documents may not be applicable. Additionally, there may be documents or evidence you can present before the consulate officer that are not listed above. The above list is the most common documents requested by immigration officers during visa interview.

For parents or individual applicants whose trip is sponsored by their children, relatives, or friends who live in United States, they should get certain documents from the sponsors. See the next section for complete list of documents required from sponsor.